London, England (CNN) -- London's Heathrow Airport will introduce more body scanners within weeks, and all British airports must have equipment to detect explosives by the end of the year, British Home Secretary Alan Johnson said Tuesday.
Johnson -- whose responsibilities include domestic security -- was speaking in response to the failed effort to blow up a plane en route to Detroit, Michigan, on Christmas Day. The suspect in the thwarted attack, Umar Farouk AbdulMutallab, had studied in Britain.
The British government had no evidence AbdulMutallab, 23, of Nigeria, had been planning an attack, and believes he was "radicalized" after he left Britain, Johnson said.
British security services investigated AbdulMutallab's communications with UK-based individuals they had under observation while he was living in London, but judged that he did not then pose a danger.
Those individuals were among 2,000 terror suspects British security agencies currently keep watch over, according to a senior British counter-terrorism source.
Johnson said the government was directing airports to carry out more random searches of passengers because metal detectors cannot spot explosives without metal parts.
British airports will also use more sniffer dogs to try to find explosives, Johnson said in a speech to the House of Commons.
"It is an issue of grave concern that the explosive device was not detected by airport security in either Lagos (Nigeria) or Amsterdam (Netherlands)," which AbdulMutallab passed through en route to Detroit, Johnson said.
The government is also considering "additional targeted passenger profiling," Johnson said.
Heathrow's operator said Sunday it would begin subjecting passengers to full body scans "as soon as practical."
"A combination of technology, intelligence and passenger profiling will help build a more robust defense against the unpredictable and changing nature of the terrorist threat to aviation," BAA, which runs Britain's largest airport, announced in a statement.
The move follows the British government's approval of electronic body scanners, which Prime Minister Gordon Brown said was necessary to combat "a new type of threat."
Speaking on the BBC, Brown said the devices will be put into place gradually, as will checks of carry-on luggage for traces of explosives for passengers boarding flights at British airports.
U.S. President Barack Obama will meet with his top security officials Tuesday in Washington to receive an update on the inquiry into security lapses that allowed the suspect to board a U.S.-bound flight.
Obama will meet with FBI Director Robert Mueller, Attorney General Eric Holder, Secretary of Homeland Security Janet Napolitano, CIA Director Leon Panetta and Secretary of State Hillary Clinton, administration officials told CNN.
Obama will get an update from Mueller on the FBI's investigation and receive information from Holder on the prosecution of the suspect in the botched Christmas Day airline bombing. Napolitano will give him an update on her review of detection capabilities, an official said.
Officials in the Netherlands and Nigeria said last week they would begin using the body scanners on airline passengers in the wake of the bombing attempt. Body scanners are currently in use at 19 U.S. airports, and U.S. officials said Thursday that 150 new ones are set to be placed in airports across the country.
Authorities say the Nigerian man tried to detonate explosives hidden in his underwear as a flight from Amsterdam, Netherlands, made its final approach to Detroit. The device failed to fully detonate, instead setting off a fire at the man's seat.
The suspect was arrested on charges of attempting to destroy an aircraft. He will face his first court hearings on Friday.
AbdulMutallab had a multiple-entry U.S. visa. His father, a leading banker in Nigeria, had warned U.S. authorities before the attack that his son might be involved with Islamic extremists, but the information failed to prompt a response such as canceling the visa.